Let the user define if a message is a request or response

[HeinrichAD]

This PR is a proposal how to solve issue #1496. Let me know what you think about it!

Instead of defining that every message from the left to the right side is always a request and every message from the right to the left side is always a response, I propose to used the arrow direction from the PlantUML diagram code.

Each arrow with the arrow direction on the right (->) is a request and each arrow with the arrow direction on the left (<-) is a response.

This way the users can define themselves what is a request and what is a response.

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closes #1496

Code

@startuml
skinparam ResponseMessageBelowArrow true
skinparam style strictuml

actor Alice as A
actor Bob as B

activate A

A -> B ++ : Request
A <-- B -- : Response

A ->> B --++ : Dispatch Task

B -> A ++ : Request
B <-- A -- : Response

deactivate B
@enduml

[arnaudroques]

his PR is a proposal how to solve issue #1496. Let me know what you think about it!

Well, your correction makes sense.

We will make some tests to see if there are no regression somewhere and we will keep you informed!

Thanks for your help.